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Merchant Shipping Act, 1951 (Act No. 57 of 1951)

Schedules

Second Schedule

Protocol of 1978 Relating to the International Convention for the Safety of Life at Sea, 1974

Annex

Chapter IV : Radiotelegraphy and Radiotelephony

Part C — Technical Requirements

Regulation 10 : Radiotelegraph installations

 

(a) Except as otherwise expressly provided in this Regulation—
(i) the radiotelegraph station shall include a main installation and reserve installation, electrically separate and electrically independent of each other;
(ii) the main installation shall include a main transmitter, main receiver, radiotelephone distress frequency watch receiver, and main source of energy;
(iii) the reserve installation shall include a reserve transmitter, reserve receiver and reserve source of energy;
(iv) a main and a reserve antenna shall be provided and installed, provided that the Administration may exempt any ship from the provision of a reserve antenna if it is satisfied that the fitting of such an antenna is impracticable or unreasonable, but in such case a suitable spare antenna completely assembled for immediate installation shall be carried. In addition, sufficient antenna wire and insulators shall in all cases be provided to enable a suitable antenna to be erected. The main antenna, if suspended between supports liable to whipping, shall be suitably protected against breakage.

 

(b) In installations on cargo ships (except those on cargo ships of 1600 tons gross tonnage and upwards installed on or after 19 November 1952), if the main transmitter complies with all the requirements for the reserve transmitter, the latter is not obligatory.

 

(c)        

(i) The main and reserve transmitters shall be capable of being quickly connected with and tuned to the main antenna, and the reserve antenna if one is fitted.
(ii) The main and reserve receivers shall be capable of being quickly connected with any antenna with which they are required to be used.

 

(d) All parts of the reserve installation shall be placed as high in the ship as is practicable, so that the greatest possible degree of safety may be secured.

 

(e) The main and reserve transmitters shall be capable of transmitting on the radiotelegraph distress frequency using a class of emission assigned by the Radio Regulations for that frequency. In addition, the main transmitter shall be capable of transmitting on at least two working frequencies in the authorized bands between 405 kHz and 535 kHz, using classes of emission assigned by the Radio Regulations for these frequencies. The reserve transmitter may consist of a ship’s emergency transmitter, as defined in and limited in use by the Radio Regulations.

 

(f) The main and reserve transmitters shall, if modulated emission is prescribed by the Radio Regulations, have a depth of modulation of not less than 70 per cent and a note frequency between 450 and 1350 Hz.

 

(g) The main and reserve transmitters shall, when connected to the main antenna, have a minimum normal range as specified below, that is to say, they must be capable of transmitting clearly perceptible signals from ship to ship by day and under normal conditions and circumstances over the specified ranges. (Clearly perceptible signals will normally be received if the R. M. S. value of the field strength at the receiver is at least 50 microvolts per metre.

 

 

Minimum normal range in miles

 

Main transmitter

Reserve transmitter

All passenger ships, and cargo ships of 1600 tons gross tonnage and upwards

150

100

Cargo ships below 1600 tons gross tonnage

100

75

 

(h)        

(i) The main and reserve receivers shall be capable of receiving the radiotelegraph distress frequency and the classes of emission assigned by the Radio Regulations for that frequency.
(ii) In addition, the main receiver shall permit the reception of such of the frequencies and classes of emission used for the transmission of time signals, meteorological messages and such other communications relating to safety of navigation as may be considered necessary by the Administration.
(iii) The radiotelephone distress frequency watch receiver shall be preset to this frequency. It shall be provided with a filtering unit or a device to silence the loudspeaker if on the bridge in the absence of a radiotelephone alarm signal. The device shall be capable of being easily switched in and out and may be used when, in the opinion of the master, conditions are such that maintenance of the listening watch would interfere with the safe navigation of the ship.
(iv)
(1) A radiotelephone transmitter, if provided, shall be fitted with an automatic device for generating the radiotelephone alarm signal, so designed as to prevent actuation by mistake, and complying with the requirements of paragraph (e) of Regulation 16 of this Chapter. The device shall be capable of being taken out of operation at any time in order to permit the immediate transmission of a distress message.
(2) Arrangements shall be made to check periodically the proper functioning of the automatic device for generating the radiotelephone alarm signal on frequencies other than the radiotelephone distress frequency using a suitable artificial antenna.

 

Normal range in miles

Metre-amperes

Total antenna power (watts)

200

128

200

175

102

125

150

76

71

125

58

41

100

45

25

75

34

14

 

1 This figure represents the product of the maximum height of the antenna above the deepest load waterline in metres and the antenna current in amperes (R.M.S. value).

The values given in the second column of the table correspond to an average value of the ratio

 

 

This ratio varies with local conditions of the antenna and may vary between about 0,3 and 0,7.

2 The values given in the third column of the table correspond to an average value of the ratio

 

 

This ratio varies considerably according to the values of effective antenna height and antenna resistance.

 

(i) The main receiver shall have sufficient sensitivity to produce signals in headphones or by means of a loudspeaker when the receiver input is as low as 50 microvolts. The reserve receiver shall have sufficient sensitivity to produce such signals when the receiver input is as low as 100 microvolts.

 

(j) There shall be available at all times, while the ship is at sea, a supply of electrical energy sufficient to operate the main installation over the normal range required by paragraph (g) of this Regulation as well as for the purpose of charging any batteries forming part of the radiotelegraph station. The voltage of the supply for the main installation shall, in the case of new ships, be maintained within plus-minus 10 percent of the rated voltage. In the case of existing ships, it shall be maintained as near the rated voltage as possible and, if practicable, within plus-minus 10 percent.

 

(k) The reserve installation shall be provided with a source of energy independent of the propelling power of the ship and of the ship’s electrical system.

 

(l)        

(i) The reserve source of energy shall preferably consist of accumulator batteries, which may be charged from the ship’s electrical system, and shall under all circumstances be capable of being put into operation rapidly and of operating the reserve transmitter and receiver for at least six hours continuously under normal working conditions besides any of the additional loads mentioned in paragraphs (m) and (n) of this Regulation.
(ii) The reserve source of energy is required to be of a capacity sufficient to operate simultaneously the reserve transmitter and the VHF installation, when fitted, for at least six hours unless a switching device is fitted to ensure alternate operation only. VHF usage of the reserve source of energy shall be limited to distress, urgency and safety communications. Alternatively, a separate reserve source of energy may be provided for the VHF installation.

 

(m) The reserve source of energy shall be used to supply the reserve installation and the automatic alarm signal keying device specified in paragraph (r) of this Regulation if it is electrically operated.

The reserve source of energy may also be used to supply—

(i) the radiotelegraph auto alarm;
(ii) the emergency light specified in paragraph (g) of Regulation 9 of this Chapter;
(iii) the direction-finder;
(iv) the VHF installation;
(v) the device for generating the radiotelephone alarm signal, if provided;
(vi) any device, prescribed by the Radio Regulations, to permit changeover from transmission to reception and vice versa.

Subject to the provisions of paragraph (n) of this Regulation, the reserve source of energy shall not be used other than for the purposes specified in this paragraph.

 

(n) Notwithstanding the provisions of paragraph (m) of this Regulation, the Administration may authorize the use in cargo ships of the reserve source of energy for a small number of low-power emergency circuits which are wholly confined to the upper part of the ship, such as emergency lighting on the boat deck, on condition that these can be readily disconnected if necessary, and that the source of energy is of sufficient capacity to carry the additional load or loads.

 

(o) The reserve source of energy and its switchboard shall be as high as practicable in the ship and readily accessible to the radio officer. The switchboard shall, wherever possible, be situated in a radio room; if it is not, it shall be capable of being illuminated.

 

(p) While the ship is at sea, accumulator batteries, whether forming part of the main installation or reserve installation, shall be bought up to the normal fully charged condition daily.

 

(q) All steps shall be taken to eliminate so far as is possible the causes of, and to suppress, radio interference from electrical and other apparatus on board. If necessary, steps shall be taken to ensure that the antenna attached to broadcast receivers do not cause interference to the efficient or correct working of the radiotelegraph installation. Particular attention shall be paid to this requirement in the design of new ships.

 

(r) In addition to a means for manually transmitting the radiotelegraph alarm signal, an automatic radiotelegraph alarm signal keying device shall be provided, capable of keying the main and the reserve transmitters so as to transmit the radiotelegraph alarm signal. The device shall be capable of being taken out of operation at anytime in order to permit immediate manual operation of the transmitter. If electrically operated, this keying device shall be capable of operation from the reserve source of energy.

 

(s) At sea, the reserve transmitter, if not used for communications, shall be tested daily using a suitable artificial antenna, and at least once during each voyage using the reserve antenna if installed. The reserve source of energy shall also be tested daily.

 

(t) All equipment forming part of the radiotelegraph installation shall be reliable, and shall be so constructed that it is readily accessible for maintenance purposes.

 

(u) Notwithstanding the provision of Regulation 4 of this Chapter, the Administration may, in the case of cargo ships of less than 1600 tons gross tonnage, relax the full requirements of Regulation 9 of this Chapter and the present Regulation, provided that the standard of the radiotelegraph station shall in no case fall below the equivalent of that prescribed under Regulation 15 and Regulation 16 of this Chapter for radiotelephone stations, so far as applicable. In particular, in the case of cargo ships of 300 tons gross tonnage and upwards but less than 500 tons gross tonnage, the Administration need not require—
(i) a reserve receiver;
(ii) a reserve source of energy in existing installations;
(iii) protection of the main antenna against breakage by whipping;
(iv) the means of communication between the radiotelegraph station and the bridge to be independent of the main communication system;
(v) the range of the transmitter to be greater than 75 miles.